get_heart_rate_zones

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description must convey behavior on its own. It clearly states that the tool 'gets' (reads) saved configuration, implying no side effects or modifications. While it does not explicitly state 'this tool does not modify data', the use of 'Get' and the context of reading configuration are sufficient to infer read-only behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise and well-structured. It uses two sentences to explain the tool's behavior and then describes the parameter in a single line. No unnecessary words or repetition are present.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description covers the tool's purpose, parameter usage, and the behavior when the parameter is omitted. It does not discuss output format or error conditions, but these are not essential for a simple getter and the output schema is separately provided. Overall, the description gives sufficient context for an agent to invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema provides no description for the sport parameter, so the description must add meaning. It specifies that the parameter is optional, gives examples of valid values (default, running, cycling), and notes the alias 'generic' for 'DEFAULT'. This adequately explains the parameter's purpose and expected input, though a full enum or link to Garmin's documentation would be more complete.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: retrieving the user's saved heart-rate training-zone configuration. It also explains the distinction between generic and sport-specific profiles, and the effect of omitting the sport parameter. The verb 'Get' and the noun 'configuration' make the function unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit instructions on how to use the sport parameter: omitting it returns all profiles, while passing a sport key returns a specific profile. It also gives examples of valid sport keys. However, it does not explicitly compare this tool to sibling tools such as set_heart_rate_zones, leaving some ambiguity about when to prefer this over others.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.